Method and system for changing a direction of establishing a telecommunication connection

ABSTRACT

A method for changing a direction of establishing a telecommunication connection between a first subscriber and second subscriber. A subscriber node is connected via a connection to a service node to request the placement of a call to the second subscriber. Once the second subscriber is contacted, the service node contacts the first subscriber and a direct connection between the first and second subscriber is established.

The invention relates to telecommunication networks. The inventionrelates particularly to a method and system for changing a direction ofestablishing a telecommunication connection in a telecommunicationnetwork in telecommunications between different countries.

The callback or recall service of known systems operates as follows. TheA-subscriber calls to the call number of the recall service (serviceprovider) and closes his phone without getting the answer for the callfrom the service system. Thereafter the service system checks thecalling party's right of use for his database and calls back to theA-subscriber, to request the number of the foreign target. The servicesystem then activates the connection to the called target or“C-subscriber” number and after receiving the answering signal, connectsthe calling A- and called C-subscribers to each other. If either partycloses, the call is ended and the service system breaks bothconnections. The calling A-subscriber is charged for the connectiontimes according to the service provider's own prices and not by therates of the foreign operator in the calling A-subscriber's locationcountry.

The recall service is effected nowadays generally as follows. TheA-subscriber calls to the call number of the recall service and closeshis phone without getting the answer for the call from the servicesystem. Thereafter the service system checks the calling party's rightof use for his data base and calls back to the A-subscriber who made thecall. The service system asks the subscriber, to which foreign C-numberhe wants to call. After this the service system activates the connectionto the called C-subscriber number and after receiving the answeringsignal connects the calling A-and called C-subscribers to each other. Iseither party closes, the call is ended and the service system breaksboth connections. The called A-subscriber is charged for the connectiontimes according to the service operator's own prices and not by therates of the foreign operator in the calling A-subscriber's locationcountry.

Concerning the service operator, a connection is formed in thisrealization mode, when the service system establish a connection to thecalling subscriber in order to ask the C-subscriber number. This isundesirable because the service operator must pay account fees for theconnection time beginning from this moment to the foreign operator ofthe A-subscriber. If the calling attempt is not finally successful, e.g.the C-subscriber number is busy, this connection with the A-subscriberhas caused expenditures for the service operator without any profits.

Another alternative comprises that the service offerer can minimize theduration of the supplementary accountable connection by breaking theconnection needed for the inquiry of the C-subscriber number immediatelyafter receiving the necessary data for the C-subscriber. Then theservice offerer calls again to the calling A-subscriber after the calledCsubscriber has answered. A weakness in this solution is that by thecoupling of the final connection a delay is caused, which depending onthe case may last from seconds to a few dozen of them. Also here extracosts are caused for the service offerer, because the accountableconnection to the third party has been established before the connectionthe customer wants is ready.

The object of the invention is to eliminate the drawbacks mentionedabove. The particular object of the invention is to set forth a methodand system when offering the recall service in countries, where callingabroad is substantially more expensive than calling from the serviceofferer's own country to the target country, so that by this method andsystem the service offerer is able to eliminate the formation of theextra connection time that only causes expenditures.

For the characteristic features of the invention reference is made tothe claims.

The basic idea of the invention is that an accountable connection isestablished only after the called C-subscriber has answered the call,whereat the whole connection time can be utilized and the serviceoperator can charge it from the calling A-subscriber. This is carriedout according to the invention so that the desired call establishingdirection and connections are formed from the public telenetwork by aseparate telecommunication connection and after the connections havebeen established they will be coupled to the public telenetwork.

Thus by the method according to the invention no costs develop for theservice operator offering the recall service in any stage of the callformation, which costs could not be charged from the call subscriber.

In the method according to the invention for changing a direction ofestablishing a telecommunication connection in a telecommunicationnetwork, in which telecommunication connections are made betweensubscribers in different countries, the A-subscriber introduces thetelecommunication connection or makes a call to the service point ornumber of the service offerer to establish a telecommunication or callto a C-subscriber in another country and in which the establishingdirection of the telecommunication connection is changed so that thetelecommunication connection is formed first from the service offerer tothe A-subscriber and further to the C-subscriber. According to theinvention another telecommunication connection is established betweenthe A-subscriber's home country and the country defined by the serviceofferer to establish connections in the desired direction between theA-subscriber, C-subscriber and the service offerer. This othertelecommunication connection is preferably formed between the collectionnode and the service node operated by the service offerer. The servicenode is generally located where the service offerer operates or in acountry that has advantageously priced foreign calls.

In one preferable embodiment the telecommunication connection introducedby the A-subscriber is connected to the collection node, and theC-subscriber's identification from the A-subscriber is received in thecollection node. The identification of the A-subscriber and theC-subscriber is transmitted to the service node using anothertelecommunication connection between the nodes. A thirdtelecommunication connection is established from the service node to theA-subscriber and a fourth telecommunication connection to theC-subscriber, and when the service node receives the answering signalfrom the C-subscriber, this is informed to the collection node and aconnection is established between the A-subscriber and the C-subscriber.In the collection node the A-subscriber's data for the right of use isadvantageously checked.

In one embodiment of the present invention the connection from theservice node to the A-subscriber is kept in a standby or call-waitingstate, until the fourth telecommunication connection between the servicenode and the C-subscriber has been established. The othertelecommunication connection will also be broken, if the connectionestablishment from the service node to the C-subscriber fails.

The system according to the invention for changing a direction ofestablishing a telecommunication connection in a telecommunicationnetwork, in which telecommunication connections are established betweenthe subscribers in different countries, includes a first terminal devicefor introducing the first telecommunications connection to the serviceproviders service node in order to establish a telecommunicationconnection to the other terminal device in another country and in whichsystem the establishing direction of the first telecommunicationconnection has been arranged as changeable so that the telecommunicationconnection is established first from the service provider to the firstterminal device and further to the other terminal device. According tothe invention the system includes the collection node in the locationcountry of the the first terminal device, which is connected to thepublic switched telephone network. Advantageously the service node andthe collection node are either telenetwork exchanges equipped withspecial software or special features or separate systems connected bynormal signalling or speech connections to the telecommunicationnetwork.

The invention will be described in the following in detail withreference to the enclosed drawing, in which a network model of therecall service according to the invention has schematically beenpresented.

The system according to the invention shown in the drawing consistsbeside the public telecommunication network of two separate node systemsor the service node 5 and the collection node 4, a separatetelecommunication connection 6 between the nodes and the servicesoftware to be adapted in the nodes. The public telecommunicationnetwork can be any combination of national or internationaltelecommunication networks, in which it is possible to formtelecommunication connections from any place to another place. Both theservice node 5 and the collection node 4 are either telenetwork centersor exchanges equipped with special programs or features or separatesystems connected by normal signalling or speech connections to thetelenetwork. The service node 5 is situated in the service offerer'scountry M3 and the collection node in the target country M1, in whichservice is offered to customers and subscribers. The telecommunicationconnection between the nodes can include for instance a stationarycoupled-in 64 kbit/s signalling connection.

The embodiment set forth in the drawing operates more precisely asfollows. The customer who has made a deal with the service offerer orhere the A-subscriber calls by the terminal device 1 the service callnumber, by which the call is directed to the collection node 4 of thetarget country M1. The collection node 4 checks the usufructuary rightdata of the subscriber in its database and receives from the customerthe actual target number to be called or the C-subscriber's number. Thecollection node 4 transmits the customer's identification, e.g. thesubscriber's telephone number, and the target number along thetelecommunication connection 6 between the nodes to the service node 5.

The service node 5 initiates separate calls to subscriber C andA-subscriber via network 7 in location M3. The call to the A-subscriberis referenced to as a “call-back” or “recall” because the service node 5is calling back the A-subscriber after the A-subscriber placed theinitial call to the collection node 4. The recall call is placed betweennetwork 7 in location M3 and network 7 in location M1 and includes theidentification data of the calling subscriber (A-subscriber) that hadbeen previously transmitted from collection node 4 to service node 5along telecommunication line 6. The recall call to device 1 remainsunanswered because the continued connection to collection of device 1 tonode 4 maintains device 1 in a standby, call-waiting or “knocking”state. When the service node receives the answering signal fromsubscriber C, this information in conveyed to the collection node 4 viadedicated line 6. Thereafter, the collection node 4 releases the device1 from the call-waiting state whereupon it is connect to network 7 atlocation M3. A direct communication connection between device 1 ofA-subscriber and device 3 of subscriber C is then established and thechargeable connection time begins.

If the time control for the waiting of the C-subscriber's answer istriggered (the called subscriber does not answer) or the C-subscriber isbusy, the telecommunication connection process between the nodes, whichhas guided the calling attempt, will be broken off as also the knockingconnection established through the public network according to thenormal practices of the telenetwork.

The invention is not restricted to concern only the exemplaryembodiments shown above, but many modifications are possible in thescope of the inventional concept defined in the accompanying claims.

What is claimed is:
 1. A method for changing direction of establishing atelecommunication connection in a telecommunication network, saidtelecommunication connection comprising telecommunication linksestablished between subscribers located in different countries, in whichmethod an A-subscriber located in a first country initiates a firsttelecommunication link to a service point of a service provider in orderto establish a telecommunication connection to a C-subscriber located ina second country, and in which method the establishing direction of thetelecommunication connection is changed from the first country to thesecond country so that said telecommunication connection is establishedfirst from said service provider to said A-subscriber and further tosaid C-subscriber, said method comprising the steps of: establishingsaid first telecommunication link to a collection node located in saidfirst country; receiving identifications of the A-subscriber and theC-subscriber in said collection node; initiating and establishing asecond telecommunication link between said collection node and a servicenode located in a third country defined by the service provider, saidsecond telecommunication link being separate from publictelecommunication networks; transmitting said identifications of theA-subscriber and the C-subscriber to said service node by using saidsecond telecommunication link; initiating a third telecommunication linkfrom said service node to the A-subscriber; initiating a fourthtelecommunication link from said service node to the C-subscriber;maintaining said third telecommunication link in a call-waiting stateuntil said fourth telecommunication link has been established; informingthe collection node when the service node receives an answer signal fromthe C-subscriber; and disconnecting the first telecommunication link andestablishing the third telecommunication link so that saidtelecommunication connection between the A-subscriber and theC-subscriber is established.
 2. The method according to claim 1, whereinuse of right data of the A-subscriber is checked in the collection node.3. The method according to claim 1, wherein said secondtelecommunication link is disconnected if establishing said thirdtelecommunication link fails.
 4. A system for changing direction ofestablishing a telecommunication connection in a telecommunicationnetwork, said telecommunication connection comprising telecommunicationlinks established between subscribers located in different countries,said system comprising: a first system access part located in a firstcountry for connecting to a first terminal device for initiating a firsttelecommunication link to a service point of a service provider in orderto establish a telecommunication connection to a second terminal devicelocated in a second country, the establishing direction of saidtelecommunication connection arranged as changeable so that saidtelecommunication connection is established first from said serviceprovider to said first terminal device and further to said secondterminal device; a collection node located in said first country forreceiving identifications of the first terminal device and the secondterminal device by using said first telecommunication link, saidcollection node being connected to a public telecommunication network; aservice node located in a third country defined by the service providerfor receiving said identifications of the first terminal device and thesecond terminal device by using a second telecommunication linkestablished between said collection node and said service node separatefrom public telecommunication networks, for initiating a thirdtelecommunication link from said service node to the first terminaldevice, for initiating a fourth telecommunication link from said servicenode to the second terminal device, for maintaining said thirdtelecommunication link in a call-waiting state until said fourthtelecommunication link has been established, for informing saidcollection node when receiving an answer signal from the second terminaldevice, and for disconnecting the first telecommunication link andestablishing the third telecommunication link thus establishing saidtelecommunication connection between the first terminal device and thesecond terminal device, said service node being connected to a publictelecommunication network.
 5. The system according to claim 4, whereinsaid service node and said collection node comprise one of exchanges andswitchboards of said public telecommunication network.
 6. The systemaccording to claim 4, wherein said service node and said collection nodeare separate systems connected to said public telecommunication networkby standard signaling and speech connections.
 7. The system according toclaim 4, wherein the system is used in direct telecommunication betweentwo countries.
 8. The system according to claim 4, wherein the system isused in the telecommunication between two countries through a thirdcountry.